The police and army in an increasingly violent Afghanistan will struggle to secure the country when foreign forces leave and the people face a corrupt presidential election in 2014, the Red Cross and a thinktank have warned.

At stake is the limited and fragile stability that has insulated Kabul and most other urban areas from more than a decade of escalating aggression since the US invasion. There are growing fears the country could face a full-blown civil war after Nato troops hand over security to the Afghan police and army, and leave.

"Time is running out," said Candace Rondeaux of the International Crisis Group thinktank, in a blunt report about the handover from coalition to Afghan troops. "Steps toward a stable transition must begin now to prevent a precipitous slide toward state collapse.

"Plagued by factionalism and corruption, Afghanistan is far from ready to assume responsibility for security when US and Nato forces withdraw in 2014."

The Long Hard Road to the 2014 Transition also argues that time is running out to ensure a 2014 presidential vote is credible or acceptable. President Hamid Karzai is due to step down in that year and powerbrokers are already jostling for position.

"It is a near certainty that under current conditions the 2014 elections will be plagued by massive fraud," the report stated. "Vote-rigging in the south and east, where security continues to deteriorate, is all but guaranteed. High levels of violence across the country before and on the day of the polls are likely to disenfranchise hundreds of thousands more would-be voters."

The last decade has brought improvements for Afghans in areas including women's rights, health and education. But for many civilians, particularly in rural areas, the steady rise of the Taliban and insurgents linked with them has also brought insecurity and misery.

"I am filled with concern as I leave this country," the outgoing head of the Afghanistan office of the International Committee of the Red Cross, Reto Stocker, told journalists in Kabul. "Since I arrived here, in 2005, local armed groups have proliferated, civilians have been caught between not just one but multiple frontlines, and it has become increasingly difficult for ordinary Afghans to obtain healthcare."

The conflict was now less brutal for civilians, however, than was the fighting that tore Afghanistan apart in the 1990s, when noncombatants were often directly targeted as a deliberate means of warfare, he said.

But many were still killed and injured, others had fled their homes to escape violence, and many Afghans who had escaped being drawn into the conflict still lived in abject poverty, extremely vulnerable to drought, flooding, earthquakes and other natural disasters.

The fragile economy was also likely to suffer, as the departure of foreign troops would hit a country dependent on war spending, from construction to fuel transportation, Stocker added.

"Hardship arising from the economic situation or from severe weather or natural disaster has become more widespread, and hope for the future has been steadily declining," he said.

Afghanistan's insecurity also appears to be fuelling its drug control problems. The country is already the world's largest producer of opium, with the UN saying on Monday the number of Afghan families growing cannabis as a cash crop leaped by more than a third last year.